Rotor and manufacturing method thereof

Abstract

A rotor includes: a rotor core in a shape of a shaft; a permanent magnet; and a connecting member interposed between the rotor core and the permanent magnet and connecting the permanent magnet to the rotor core. The connecting member contains a thermally conductive filler made of a non-magnetic material. Only ends of the filler have magnetism, and the ends are in contact with either or both of the rotor core and the permanent magnet.

What is claimed is: 
     
       1. A method for manufacturing a rotor including a rotor core in a shape of a shaft, a permanent magnet, and a connecting member interposed between the rotor core and the permanent magnet and connecting the permanent magnet to the rotor core, the method comprising:
 magnetizing ends of a thermally conductive filler made of a non-magnetic material; 
 placing the permanent magnet in a mold; 
 injecting a resin containing the thermally conductive filler into the mold such that the resin is molded around the permanent magnet; 
 bringing an electromagnet close to the resin containing the thermally conductive filler from an outside of the mold such that the thermally conductive filler is oriented, and then curing the resin; 
 removing the mold from the permanent magnet with the resin containing the thermally conductive filler; 
 inserting the permanent magnet with the resin containing the thermally conductive filler into one slot of the rotor core in an axial direction; and 
 connecting the rotor core and the permanent magnet via the resin containing the thermally conductive filler and bringing the ends of the thermally conductive filler into contact with either or both of the rotor core and the permanent magnet. 
 
     
     
       2. The method according to  claim 1 , wherein the ends of the thermally conductive filler are magnetized by bending the thermally conductive filler. 
     
     
       3. The method according to  claim 1 , wherein the thermally conductive filler is provided only in the resin located between the permanent magnet and the rotor core.